DESCRIPTION: If a means-end deficit cannot explain infants? search failures with hidden objects, then why do infants succeed with objects hidden by darkness, which does not require means-end skill? The proposed work addresses this question by testing the graded representations account, derived from cognitive neuroscience. According to this account, infants? representations gradually strengthen with development to support success on a greater range of object permanence tasks. Infants search in the dark before they search in the light because darkness interferes less with a fragile object representation than a visible occluder does. The first project will test whether the dark advantage is genuine by controlling incidental differences between light and dark studies that may favor search in the dark. The second project will test the graded representations account against the means-end deficit account by manipulating whether 6.5-month-olds are presented with hidden objects available by direct reach or a means-end sequence, in either the dark or the light. The third project will test the graded representations account by manipulating factors believed to affect the strength of object representations, such as amount and type of experience with the object. The long- term objective is to increaseknowledge about cognitive development in normal infant populations.